1. all MMOs are time sinks. This is an undeniable fact. An MMO has no ending (until they turn the game off) so the content is meant to be a time sink that players invest their time into.

The fact that people want to rush to 50 is not the fault of the company, but the player. If content is meant to last until next patch, and players want to zerg through it in half the time, then that's there fault and they will have to wait for the next patch like everyone else while grinding endgame stuff. SE said content would be released every 3 months. Not their fault you wanted to blitz through it in 1.5 months. Have fun with your endgame.

2. The main "sin" is the entitlement of players that think that the company needs to run on the player's schedule. This couldn't be further from the truth, and it irritates elitists and those with entitlement issues. "I cleared the content already, I shouldn't have to be left grinding until there's more content. Give me more."

3. Grinding is a part of every single MMO ever in existence. There has never been endgame where they say "here, enjoy getting into the hardest content right off the bat." NO. You have to grind through easier content to make yourself useful in harder content so you don't get thrown around like a ragdoll and hurt your team.

4. The summary of OP's "instant gratification":